Some questions about beam profiles & screeds

[Boyblue]

Is there a difference between the straight T beam and the one that looks like a capital I with nods at the top that almost mirror the bottom?  Is it just a style thing or are there critical differences that should be considered when selecting?  Are there less consequential differences like might one or the other fit more snugly or require more screed material?  Is one more popular, or more commonly used?

When no screed is detailed on a beam span chart, does it mean that a screed is unnecessary, or is it that none can/should be applied?

 

[nod]

Some pics would help 

But I would imagine that all BB are the same 
 

[Boyblue]

1 hour ago, nod said:

Some pics would help 

But I would imagine that all BB are the same 
 

Those are the two styles to which I was refering.  It may be an efficiency thing, less material means less weight and less cost, right

[Mike]

The top one is no doubt designed for greater loads / longer spans. Apart from that, no practical difference.

 

A screed is normally required to even up the levels - the beams curve upward a little in the centre.

[Boyblue]

2 hours ago, Mike said:

The top one is no doubt designed for greater loads / longer spans. Apart from that, no practical difference.

 

A screed is normally required to even up the levels - the beams curve upward a little in the centre.

Thanks, I read that you can do a 25mm screed if you use bonder, is this something that is common? Would you advise this?

[nod]

I’ve installed BB on two houses now 

Super Simple The bottom one is typical I wasn’t aware of any different types I would image the top one is for longer unsupported slabs like basements In any case screeding would be exactly the same on both 

[Mike]

16 hours ago, Boyblue said:

I read that you can do a 25mm screed if you use bonder, is this something that is common? Would you advise this?

No, it's not that common, but possible If the product says it's suitable for the purpose.

[Boyblue]

10 hours ago, nod said:

I’ve installed BB on two houses now 

Super Simple The bottom one is typical I wasn’t aware of any different types I would image the top one is for longer unsupported slabs like basements In any case screeding would be exactly the same on both 

Thank you that is helpful info.  Based on your experience what's the longest span would you suggest be done manually and I'm wondering that for as long as the Brits have been doing beam & block why aren't there buggys or trollys made for moving beams?

[Boyblue]

19 minutes ago, Mike said:

No, it's not that common, but possible If the product says it's suitable for the purpose.

Thanks Mike, I prefer to stay away from uncommon solotions, I'll have to ask the engineer to inclide the 50mm screed in the calculation.

[nod]

16 minutes ago, Boyblue said:

Thank you that is helpful info.  Based on your experience what's the longest span would you suggest be done manually and I'm wondering that for as long as the Brits have been doing beam & block why aren't there buggys or trollys made for moving 

Not sure of the maximum span 

but I would put as many sleeper walls under as possible 

To reduce the bounce 

A lot of the  big companies use a mobile crane 

I used a borrowed digger with forks 

[Mike]

31 minutes ago, Boyblue said:

why aren't there buggys or trollys made for moving beams?

A 2-wheeler like this would be fine: https://www.evosupplies.co.uk/shop-buy-furniture-skates-moving-dollies/construction-trolley/

But, as @nod says, they're usually placed mechanically.

[nod]

3 minutes ago, Mike said:

A 2-wheeler like this would be fine: https://www.evosupplies.co.uk/shop-buy-furniture-skates-moving-dollies/construction-trolley/

But, as @nod says, they're usually placed mechanically.

The problem you would have is The need lifting over the outer skin of brickwork 

[Boyblue]

17 hours ago, nod said:

A lot of the  big companies use a mobile crane 

I used a borrowed digger with forks 

So the options are to build more internal walls to keep the spans to a managable length or rent a crane.  manpower against the price of crane rental.  About how long would it take to place beams on a 100 m² foundation, give or take?

[Alan Ambrose]

>>> crane

 

Or depending on your beam length and weight a telehandler?

[Mr Punter]

4m maximum spans are fairly standard with beam and block or timber joist.  Any longer and the beams or joists get heavy and the floor can be more bouncy.

 

With a crane, 3 people would be able to do the floor beams and blocks in a day.  If you are hiring a crane, get as much heavy material loaded out as possible to make full use on the day.

[Boyblue]

On 15/01/2025 at 13:17, Mr Punter said:

4m maximum spans are fairly standard with beam and block or timber joist.  Any longer and the beams or joists get heavy and the floor can be more bouncy.

I notice that your foundations have lots of interior walls that make beam and block installation easier, we don't have that.

 

On 15/01/2025 at 13:17, Mr Punter said:

 

With a crane, 3 people would be able to do the floor beams and blocks in a day.  If you are hiring a crane, get as much heavy material loaded out as possible to make full use on the day.

Good point

[Canski]

Due to the machine already being on site, we usually use a telehandler for the beam and block with a single chain attached to the forks to enable us to spin the beams to get them lowered into roughly the correct position. To speed things up we lift several beams in at once and then manually move them into the correct position. You need to ensure that they are lifted and not slid to prevent damage to the DPC. The placing of the beams doesn’t take too long maybe 33% of the time. The filing in with blocks about 33% and the rest of the time is allocated to infilling the perimeter edges and any other gaps and grouting. A team of 3 would take  2 to 3 days depending on access. If the telehandler can’t reach the rear of the property we use a dolly to move the beams over the infilled blocks. 
 

A crane is quicker but more costly. 

Edited 9 hours ago by Canski